The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, a. [L. emaciatus, p. p.]
   Emaciated. "Emaciate steeds." --T. Warton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, v. i. [imp. & p. p. Emaciated; p. pr.
   & vb. n. Emaciating.] [L. emaciatus, p. p. of emaciare to
   make lean; e + maciare to make lean or meager, fr. macies
   leanness, akin to macer lean. See Meager.]
   To lose flesh gradually and become very lean; to waste away
   in flesh. "He emaciated and pined away." --Sir T. Browne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, v. t.
   To cause to waste away in flesh and become very lean; as, his
   sickness emaciated him.
   [1913 Webster]

WordNet (r) 3.0 (2006):

emaciate
    v 1: cause to grow thin or weak; "The treatment emaciated him"
         [syn: waste, emaciate, macerate]
    2: grow weak and thin or waste away physically; "She emaciated
       during the chemotherapy"